Web registering device



Oct. 5, 1937. E. F. CORNOCK 2,095,125

WEB REGISTERING DEVICE Filed April 28, 1936v 5 Sheets-Sheet 1 INVENTOR Farr/4 90 J. Cam om TTORNEYS Oct.5,1 937. E. F. CORNOCK 2,095,125

WEB REGISTERING DEVICE Filed A ril 28, 1936 3 Sheets-Sheet 2 INVENTOR flow/400K (m/wax TORNEYS Oct. 5, 1937. E. F. CORNOCK ,0

' WEB REGISTERING DEVICE Filed April 28, 19:56 s sheets -sheet s I INVENTOR BY Eon/M0 Coflwocx TORNEYS Patented Oct. 5, 1937 UNITED STATES PATENT OFFICE WEB REGISTERING DEVICE Application April 28, 1936, Serial No. 76,734

7 Claims.

The present invention relates to improvements on web registering devices of the general type in which adjustments in the longitudinal position of a web'are periodically made in accordance with the response of a detecting device such as a photoelectric cell, electrical contacts made through perforations or specially treated areas of the web, or suction devices acting through perforations in the web. One such device is shown in the prior patent to Smith 8: Cornock, 2,035,201, March 24, 1936, to which reference will be made herein for a description of parts of the apparatus which do not in themselves form a part of the present improvement. In the operation of such prior devices it has been found that on account of the difliculty of securing accurate setting of the normal forward travel given to the web, corrections were necessary with undesirable frequency. Particularly in connection with devices employing a continuously traveling web as distinct from devices in which the web has an intermittent forward movement, the forward travel given at each cycle of the machine operation has previously been adjustable only by changing the driving gears or by means of a friction or belt drive.

The first of these adjustment means has the disadvantage of being variable only in steps, so that unless the length of web to be fed was exactly proportional to the gearing available the forward travel of the web would not be correct. The second has the objections of bulk and lack of positiveness.

In accordance with the present invention the forward motion of the web is derived from three sources. 'I'hefirst of these isa gear drive, preferablyfltted with change gears so that accommodation can readily be made for different sizes of sheet. The second is a ratchet and pawl drive provided with an adjustable stroke and operative on every cycle irrespective of whether correction is required or not. This drive serves to bring the rough adjustment given by the change gears to the exact constant feed desired. It can be changed by-very small amounts if desired, and

may be adjusted to maintain the desired feed as atmospheric conditions change the lengths between indicia on the web. The third feed is a ratchet and pawl feed controlled by the indicia and operative to introduce a correction into the feed in the manner described in the prior patent referred to. The first and third feeds are substantially the same in their details as in the prior patent, and will be described in somewhat less detail for that reason. The invention will now be described with reference to the accompanying drawings, in which Fig. 1 is a side elevation of a paper feeding mechanism embodying the present invention;

Fig. 2 is a detail, looking from the left in Fig. l, of the intermittently acting portions of the paper feeding mechanisms, other parts of the apparatus being removed for the sake of clearness;

Fig. 3 is a detail of certain parts shown in 10 Fig. 1;

Fig. 4 is a longitudinal section through the differential gear;

Fig. 5 is a detail section on line 5-5 of Fig. 2; and

Fig. 6 is a detail section on a larger scale taken on line 6-6 of Fig. 2.

The present device is adapted to operate upon a web 20 of paper or other material, this being,

supplied from a reel 2| journaled upon brackets 20 22 which extend from the main frame 23. After leaving its reel the web 20 passes over the usual slack take-up roll 24 mounted for swinging movement upon arms 25 pivoted to the frame at 26 and urged in a counterclockwise direction as viewed 25 in Fig. 1 by any suitable spring mechanism. The web then passes guide rolls 29 that position it for the scanning operation of the photo-electric cell or electric eye contained within a housing 30 and cooperating with a light source 3|. 30

The web then passes between upper and lower feed rolls 40 and ll respectively. The two rolls I are geared together by pinions (not shown), the

drive being through the lower roll as will be explained. Situated beyond the feed rolls is a 35 suitable knife mechanism fully described-in the patent referred to. Finally, the severed sheet is seized between feed belts 41 and 48 which may form a part of a sheet forwarding mechanism.

It will be convenient before taking up the web 40 controlling mechanism to consider the driving mechanism for the feed rolls, it being through this driving mechanism that control of theregistration of the web is accomplished. At one end the shaft 49 (Fig. 4) which bears the lower feed 45 roll 4| is extended through the frame, and at a distance from the outer side of the frame has a reduced portion 50 on which is keyed a pinion 5| having a hub portion journaled in an end plate 52 secured to a housing 53* by dowels 54 and by 50 studs 55. At its inner side this housing has a hub portion 56 journaled upon a sleeve 51 which in turn is journaled upon bushings 58 on the shaft 49. A gear 59 is keyed to the sleeve 51 and is rotated at constant speed by mechanism 55 to be described, turning the sleeve at the same constant rate. The outer end of the sleeve is formed with a pinion 6i meshing with a series of differential pinions 62 freely. mounted upon the 5 studs 55. A second series of differential pinions 63 are formed integral with those of the first series, and are of somewhat larger size. These latter pinions mesh with the pinion 5| on the end of shaft 49. It will be seen that if the .housl ing 53' is held stationary the gear 59 will, through the pinions 6|, 6!, 63, and cause the shaft 49 to turn in the same direction and at a constant relative speed dependent upon the number of teeth on the several gears. If the housing is given 5 a bodily rotation the difierence in the sizes of the pinions 62 and 63 will cause a relative advance or retardation of the shaft 49 depending upon the direction in which the housing is moved. In the present case the housing is rotated in one direction only, the feed rolls being set to'feed a length of web over or preferably under the correct length and the housing being rotated periodically in a single direction with a frequency dependent upon the degree of correction required. Rotation of the housing for corrective purposes is obtained by a ratchet and pawl mechanism receiving its power from the main drive and controlled in its operation by the photo-electric cell which scans the web. Projecting from the machine frame is a non-rotating stud HI which may be formed from the end of one of the tie bars "which hold the frame assembled. A pawl II (Fig. 3)- is pivoted at H to an arm 19 pinned to the stud so that it does not rotate. A spring 14' presses on the pawl to hold it against a wide ratchet 15 which is free on the shaft and has" fixed to it a gear I6 in mesh with a gear 11 on the housing 59. The pawl ll serves as a holdback to prevent movement of the ratchet, and 4 0 consequently of the housing, in a backward direction.

' To the rear of the ratchet an arm 16 (Fig. 5) is freely movable'on the stud. One end of this arm is provided with an arcuate slot 19 in which an adjustable pivot 66 is clamped by a nut 6| (Fig. 2). A link 62 joins this pivot with a crank pin 89 carried by a crank 84 upon the end of a rotating shaft 66. A sprocket 91 (Fig. 1) on this shaft is connected by a chain 66 with a sprocket 89 on a drive shaft 96, which may conveniently be a part of the wrapping machine or other mechanism to which the paper feed is applied, so that the shaft 96 is driven continuously at a constant rate. The other end of the arm I6 isprovided with a pivot 9| for a pawl 92 held against the ratchet l5 bya spring 93 and having a tail 94 by which the pawl may be held out of contact with the ratchet.

Situated still further to the rear on the stud I9 is a member 95 (Figs. 2 and 6) free on'the stud and constantly urged in an anti-clockwise direction (as viewed in Figs. 5 and 6) by a spring 96 coupled between arm 91 on the member 95 and a clip 98 (Fig. 1) on the frame. A second arm 99 on the member 95 bears an abutment III which,

when the spring 96 is left free to act, rests constantly against the pawltail 94 and keeps the pawl out of contact with its ratchet. A third arm III is recessed to receive a sliding dog I62 pressed outwardly by a spring. This dog is? adapted for engagement with a plate I95 carried on a bell crank I66 pivoted at I61 to the end of an arm I08flxed against rotation on the stud Ill.

. On the other end of the bell crank is an adjusta'ble abutment in the form ,of a screw I99 held in place by a lock nut H0. This screw is positioned so as to be contacted with by a finger Ill projecting from the armature 2 of a standard relay or contact-closing type of electromagnet H3 which is in the circuit controlled by the photo-electric cell. The .bell crank I96 is preferably limited in its angular motion by a fixed abutment 4 formed on the arm l08,-and by a screw I I5 threaded into a lug 6 on the arm and held in place by a lock nut I I1.

Whenever a current is established in the electromagnet by the photo-electric cell, as is described in said prior patent, the finger III will act on the bell crank to swing the plate l =into its dotted line position in the path of the dog III! as described in said prior patent. The closure of the circuit through the magnet is not critical in its timing, since this circuit is arranged to remain closed for a considerable part of the cycle. Provided that the circuit through the magnet is closed during the inactive or clockwise rotation 1 of the pawl arm and remains closed until the pawl starts its active or counterclockwise movement the action will be the same. In-any case the sole direct function of the magnet is to tilt the plate into the path of the dog I92, an operation requiring little expenditure of power as the bell crank may be made nearly evenly balanced. If

the dog has not by that time passed the plate-in its inactive stroke it is permitted by its spring to ride over it, and when the pawl carrier starts.

its counterclockwise motion the dog will be caught by the edge of the plate and prevented from further motion. It will be understood that except when the plate is shifted into this position the spring 96 will keep the abutment I09 against the tail 94 of the pawl-and the members 16 and' 95 will move as a unit with the pawl held out of engagement with the ratchet. When the plate holds the member 95 against movement, however, the abutment I00 can no longer restrain the pawl; and in that case the ratchet is engaged by the pawl and is rotated to cause a corresponding rotation of the housing 53 and therefore a correction in the angular position of the feed rolls. The correction applied is predetermined in amount and is always in a single direction, the amount of correction given to the rolls being governed by the position of pin 99 in the curved slot 19. For a given setting of the pin 96 the correction is constant in amount, and will vary in the frequency of its application as may be required to keep the web in register. One advantage of thepresent invention, as will be more fully explained later, is that the normal feed of the web can be brought more nearly to that of the correction can bemade smaller to accom-' modate this more accurate feed. This results in more accurate and closer regulation than has.

heretofore been possible.

In order to varythe amount of rotation given to the web feed rolls duringeach cycle, and thereby to control the length of sheet cut, a change speed gearing is provided for driving the lower feed roll 4|. It will be recalled that the drive for this roll was obtained from a gear 59 will be apparent from a comparison of the sizes acting through the differential gearing described in connection with the feed correcting mechanism. This gear meshes with a gear I45 rotatable on the end of an arm I46 adjustably held to the machine frame at I41. A gear l48 is fixed to gear I45 and meshes with a gear I49 on a driving shaft I50 which receives a constant rotation from the machine to which the sheet feed is to be applied. By changing these gears any desired approximate rate of web feed can be obtained. i

In the present invention mechanism is provided for supplementing the constant feed given by the change gears by an adjustable feed which can be varied to give any desired degree of accuracy. The change gears can of course be adjusted only by definite increments, and it is necessarily a somewhat slow operation to remove the gears and substitute others in order to obtain the feed desired. The change gear method of adjustment is desirable in order to obtain sheets of a considerable length, since an oscillatory feed like a ratchet and pawl is limited in the amount of motion that can be given by the feed rolls at any stroke unless the drive is geared up and the effective adjustment of the mechanism thereby made so coarse as to be practically equivalent to the coarse. adjustment obtainable through the change gear mechanism. By the present invention, however, the ratchet and pawl mechanism is called upon to produce only a small motion of the feed rolls at each cycle of the machines operation, and thus a variation in the stroke given to the pawl will-produce a fine variation in the rotation of the feed rolls. The fineness of this adjustment is not impaired in any way by the length of the sheet which is to be fed. All major shifts in the length of the sheet are taken care of by the change gear mechanism, and only a constant range of adjustment is taken care of by the adjustable pawl and ratchet mechanism to be described. As an example, if the length of sheet is to be 8 inches the change gear mechanism will be set to produce about 8 inches of the feed with only the remaining quarter (minus a sumcient amount to give a constant necessity for periodic uni-directional correction) supplied by the adjustable ratchet and pawl mechanism. The details of this adjustable mechanism will now be described.

Carried upon the stationary shaft 10 just to the rear of the member 13 is a bell crank 200 having a bent arm 20I (Figs. 2 and 3) having a pawl 202 pivoted to it at 203 and pressed by a spring 204 against the wide ratchet 15 with which the corrective pawl 92 also contacts. A pivot 205 on the bell crank 200 is joined by a link 206 with a pivot 201 adjustably secured as by a nut 208 in a slot 209 formed in a crank member 2I0. This member .is pinned at 2 to the pivot 83 which is also pinned at 2I2 to the crank member 84. The effect of this construction is to cause the crank members 2I0 and 84 to move as a unit in the manner of an offset crank shaft. The pivots 83, to which the link 82 is coupled, and 201, to which the link 206 is coupled, are arranged substantially 180 from each other so that one of the links is moving up while the other is moving down. The pawls 92 and 202 thus act on the ratchet alternately so that the operation of one is not masked by the operation.

of the other. Any desired angular motion "of the pawl 202, from zero to the maximum permitted by the length of the slot 200, may be obtained by shifting the movable, pivot 201. It

of the gears 16 and 11 that the feed rolls will.be moved a lesser angular distance than the angular motion given to the pawl 202. This permits a very accurate adjustment of the constant feed given at each cycle to the feed rolls, the smallest adjustment possible being much smaller than the pitch distance between successive teeth on the ratchet 15.

The apparatus has been described in some detail in order to make the construction and operation of the preferred form of the invention readily understood. The arrangement and construction of the several parts may, however, be varied within wide limits without departing from the scope of the invention as defined in the accompanying claims. It will also be apparent that the invention may be applied to an intermittent rather than a continuous type of paper feed by imposing an intermittent drive upon the gear 59 through the change gear mechanism. In either case the same advantage will be retained of being able to adjust the constant feed given at each cycle within very narrow limits, so that the frequency of the correction and its magnitude may both be cut down below what was possible with prior devices intended for the same general purpose.

I claim:

1. A web registering device comprising web feed rolls, means for imparting a cyclically constant advance motion to the feed rolls, adjustable means for changing by a constant amount in each cycle the advancing motion of the feed rolls given by the first means,- and indicia controlled means operative to introduce a corrective variation into the advance of the feed rolls when required by the condition of register of the web.

2. A web registering device comprising web feed rolls, means for impartinga cyclically constant advance motion to the feed rolls, adjustable means for imparting to the feed rolls at each cycle a further constant advance, and indicia controlled means operative to impart a corrective further advance motion to the feed rolls web.

3. A web registering device comprising web feed rolls,'a three element difierential gear, one element of which is connected to the feed rolls, means. for imparting to a second element of the differential gear a cyclically constant advance motion, adjustable means for imparting at each cycle a constant motion to a third element of the differential gear, and indicia controlled means operative to impart a corrective motion to said third element when required-by the condition of register of the web.

4. A web registering device comprising web feed rolls, a three element gear, one element of which is'connected to the feed rolls, means for imparting to a second element of the differential gear a cyclically constant advance motion, adjustable intermittently acting means for imparting at each cycle a constant motion to a third element of the differential gear, and indicia controlled means operable during the periods of inaction of said intermittently acting means to impart a corrective motion to said third element when required by the condition of register of the web.

5. A web'registering device comprising web feed rolls, a three element gear, one element of which is connected to the feed rolls, means for gear a cyclically constant advance motion, means including a ratchet and variable throw pawl for imparting at each cycle a constant motion to a third element of the diflerential gear, and indicia controlled means operative to impart a corrective motion to said third element when required by the condition of register of the web.

6. A web registering device comprising web feed rolls, a three element diflerential gear, one element of which is connected to the feed rolls, means for imparting to a second element of the diflerential gear a cyclically constant advance motion, ratchet means geared to a third element of the diiierential gear, a pair of pawls engageable with said ratchet means, means for oscillating said pawls alternately in their ratchet forwarding directions, means for adjusting the oscillatory motion or one of said pawls, and indicia controlled means for controlling the engagement of the other of said pawls with the ratchet means.

'7. A web registering device comprising web feed rolls, a three element difierential gear, one element of which is connected to the feed rolls, means for imparting to a second element 'of the difierential gear a cyclically constant advance motion, ratchet means geared to a third element of the difierential gear, a pair of pawlsengageable with said ratchet means, means for oscillating said pawls alternately in their ratchet forwarding directions, means for adjusting the oscillatory motion of the pawls independently of each other, and indicia controlled means for controlling the engagement of one of said pawls with the ratchet means.

' EDWARD F. CORNOCK. 

